Waves and nem has a different use. But i prefer you buy waves because of waves ng launch. And it claimed to be the fastest blockchain transaktion ever. I predict waves could be reach $20 in januari 2018 if bitcoin still climbing. And when bitcoin going to correction mode many whale will move their money to waves because of its dex and fast transaction.
Nem blockchain make transaktions during 1-3 seconds. Grew in more than 100 times during this year. Make x4 in dollars during last month. Nem is better for investing